Cross Layer Design for Mobile IP Handoff

Wireless and mobile Internet access has brought increased significance to the evolution of 3G packet-based communications and a vision of a future based on all-IP networking. To reduce handoff latency and signaling cost are two major issues. Certain link-layer technologies are capable of providing various link status information to the IP module. It has been identified that receiving explicit hints from the layer 2 (link layer) would expedite the layer 3 (network layer) movement detection process, which in turn will reduce the handoff latency. In this paper, a likelihood function based method for implementing link layer hints is defined. Then the function is used to estimate layer 3 movement in two levels: (1) a mobile node is moving into a new subnet and (2) a mobile node is requiring an inter-system handoff. Next, the use of the likelihood function is applied to a pre-registration inter-system handoff protocol. Finally, performance analysis demonstrates significant gains in signaling cost from the proposed method.